A Study of Acute Graft-Versus-Host Disease (GVHD) in Patients Undergoing Allogeneic Stem-Cell Transplantation

This is a Phase II, randomized, double-blind, placebo-controlled, multi-center study to evaluate the feasibility of the use of PRO 140 as an add-on therapy to standard GVHD prophylaxis treatment for prevention of acute GVHD in adult patients with AML or MDS undergoing allogeneic HCT. In this study, 60 subjects will be randomized to receive either PRO 140 or placebo in a 1:1 ratio (i.e., 30 subjects per arm). PRO 140 or placebo will be administered as a 350 mg subcutaneous injection on Day -3 or Day -2 prior to stem cell infusion, on the day of stem cell infusion (Day 0), and then weekly for 30 days (at Week 1, Week 2, Week 3 and Week 4) after which it will be administered every two weeks for up to 100±7 days (at Week 6, Week 8, Week 10, Week 12 and Week 14). Subjects will return to clinic for two Follow-up visits at 2 weeks after the last treatment visit, and one year after the first treatment visit.